Test connector system



4 Sheets-Sheet l E. H. GATZERT TEST CONNECTOR SYSTEM ATTORNEY April 22, 1958 Filed Sept. "7, 1955 April 22, 1958 E. H. GATZERT 2,831,930

TEST CONNECTOR SYSTEM Filed Sept. '7, 1955 4 Sheets-Sheet 2 l 6 5 WM E 2 2 4 w 4 w 3\ wm 1f w liv l!!! Il IV 1 l2 Bw l 3 H A o 0 2 I I I I l l l a I I I I I I l I i I I l I I Il H u q A m :n Ayia H M O+ O l llw m 1 1 l l l ||l||. lllllll II w m m 5 u a u. 2 SM R s ARS T R S H RET EHI. PTU d oom mmm April 22, 1958 E. H. GATzr-:RT

TEST coNNEcToR SYSTEM 4 Sheets-Sheet 4 Filed Sept. -7, 1955 MULTIPLED TO OTHER SWITCH s E .l. W RS mm mw LN O MC DP WU 9 8 ,.Dm my 2 2 Y@ /f l N N M O O S R VA V| X United Sttes Patent TEST coNNncron svsrniw Ernest H. Gatzert, Rochester, N. Y., assigner to General Dynamics Corporation, a corporation ot lteiaware Application September 7, 1955, Serial No. 532,992

12 Claims. (Cl. 179-1752) The present invention relates to telephone systems, and more particularly to improvements in impulse responsive automatic switching systems as used for dial telephone operation.

It is a principal object of the present invention to provide an improved, simpler, and more economical type of automatic telephone switching system to be used for special purposes.

As is well known, automatic telephone systems still require the use of an operator for many specialized functions. One of the duties which an operator is called upon to perform in the operation of an automatic telephone system is to verify the busy condition of a line. lt seems unavoidable that through occasional failures of the equipment, the automatic switching equipment will not operate properly in that a desired line appears to be busy when in actuality the line is idle. As mentioned previously, when such condition arises, a test operator is required to operate a special verification train of impulse responsive automatic switches to seize the apparently busy line and thereby monitor the line to determine if the line is actually busy. Also, it is sometimes desirable for a toll operator to be able to seize a busy line and advise the parties on the line that the line is needed for a long distance or emergency call.

Prior to this invention, the aforementioned verification train of impulse responsive automatic switches has included the usual selector and connector switches and associated control circuits with the additional provisions for switching the connector through to a busy line instead of returning busy tone and preventing the switchthrough.

An important object of this invention is to provide a simplified form of impulse responsive automatic switch train whichmay be advantageously used for busy verification functions.

Another important object of the invention is to provide an improved impulse responsive automatic switch train which may be used to select any one of a large number of lines arranged in a plurality of groups of lines such as would ordinarily require both selector and connector switches and associated control circuits but having, ac-

cording to the invention, only one control circuit with relays for the operation of all of the various selector and connector switches.

Other objects, advantages, and the attending features of the invention will be apparent with reference to the following specication and drawings in which:

Fig. 1 is a block diagram of the impulse responsive automatic switching system of the invention as particularly used for a verification switch train; and

Figs. 2-4, when taken together and placed side by side in order from left to right, show a schematic wiring diagram of the circuit details of a preferred form of impulse responsive automatic switching system shown in the block diagram of Fig. l.

Referring to Fig. 1 of the drawings, the verification connector control circuit is shown by the block outline and respective ones of impulse responsive group connector P 1Ce tion 21 may be connected through the usual telephone circuits including cord circuits and trunk circuits (not shown) which are connected by the usual tip, ring, sleeve, and hunt sleeve conductors PL2-25 to the verification connector circuit 10. The verification connector circuit 10 includes the usual impulse responsive relays and other control relays to respond to the dialed impulses from the verification test operator position in order to extend the desired connection to a selected one of the impulse responsive group switches 11-20 and a desired line as may be selected by the particular impulse responsive group switch. Various talking and control conductors including tip conductor 26, ring conductor 27, sleeve conductor 28, X-olnormal conductor 29, Y-off-normal conductor 30, and Z-conductor 31 are connected in multiple between the verication connector circuit l0 and each of the impulse responsive group connector switches 11-20. In addition, one of the individual control conductors XMtl-XM9 is connected to a respective one of the impulse responsive group connector switches 11-2tl. An impulse responsive selector switch, generally shown at 32 within the Verication circuit block outline 11, is arranged to be operated to select a particular one cf the individual control conductors XMO-XM9.

Still referring to Fig. l of the drawings, a general description of the operation of the impulse responsive automatic switching system cf the invention is as follows. The verification test operator seizes the verification connector circuit 10 in the usual manner and the iirst group of dial impulses following such seizure are caused to operate the impulse responsive selector switch 32 to select a particular one of the individual control conductors XMO-XM9. Depending upon the number of impulses in the aforementioned rst group of dial impulses, the selector switch 32 will through its selection of a particular one of the control conductors XMtl-XM9 cause a respective one only of the impulse responsive group connector switches 11-20 to respond to the second group of dial impulses which is thereafter connected over the respective selected one of the individual control conductors XMO-XM9 to the respective impulse responsive connector switch. Thus, a selected one of the impulse responsive group connector switches lil-Ztl will move off-normal in a first direction in the first process of selecting a line in the group of lines to which it has access. Due to the oitnormal position of the selected impulse responsive group connector switch, the third group of dial impulses, which is thereafter connected over the multipled control conductor XON to all of the group connector switches 11-20, causes only the ott-normal one of the impulse responsive group connector switches to move in the second direction and select a desired line in the group of lines. lt should be apparent that the impulse responsive automatic switching system of the invention as described above results in a saving in relays and control circuits due to the combinations of individual and multiple control conductors from the single connector control circuit lil to the plurality of impulse responsive group connector switches: 1l1--2t). Of course, such a system has its primary utility in a verification switch train since there are no provisions for the extension of more than one call at a time to any of the groups of lines.

Reference is now made to Figs. 2-4 of the drawings for a detailed description of the circuit features of a presently preferred form of the invention. The power source (not shown) is indicated by the positive and negative symbols, which may also be referred to as `ground and battery, respectively. The tip, ring, sleeve and HS conductors from the preceding telephone and verification test operator circuits, which were identified as conductors 22,-25, respectively, in Fig. l of the drawings, are identied `with corresponding numerals at the upper left hand corner of Fig. 2 of the drawings. To seize the verification connector circuit indicated as 10 in Fig. l of the drawings and shown in detail by Figs. 2 and 3 of the drawings, a loop is closed over the tip and ring conductors 22 and 23 to cause the calling bridge relay l0@ to operate from ground through its upper winding 100A and the calling line loop circuit to its lower winding lllllB and battery. It might be pointed out at this time that Fig. 4 of the drawings shows in detail only one of the plurality of impulse responsive group connector switches as indicated as llil on `lFig. l ofthe drawings.

The operation or' the calling bridge relay lil@ closes pulsing contacts lill. and connects a circuit from ground through the coil of the release delay relay lli) to battery and causes the operation of such relay. The operation of the release delay relay llt? closes contacts` lllli to connect ground to the sleeve conductor 2d and identity the verification connector circuit as busy. rl'he previously mentioned operation of the calling bridge relay lull to close pulsing contacts lill also causes the X-delay relay 12u to operate through the circuit from battery, relay coil winding 12h/, normally closed oit-normal contacts MZill, and operated contacts lill to ground. The operation ot X-delay relay closes contacts 121 to prepare a pulsing path to the selector switch operating magnet MX. Upon the first dial impulse in the iirst group of dial impulses, the calling bridge relay lull is momentarily restored to close the pulsing contacts 192 connecting ground through operated contacts lllZ and the aformentioned operated contacts lill to the operating coil MX and battery or the selector switch generally shown at M/L'lll. Thus, as the calling bridge relay lili? operates and restores in response to the impulses of the first group of dial impulses, the selector switch magnet MX is alternately energized and deenergized to step the selector switch wiper M202 to a corresponding position in contact with a respective one of 'the individual control conductors XM`M9- Also upon the first restoration ot' the calling bridge relay litlti in response to the iirst dial impulse, the lower winding HSB of the X-delay relay l2@ is energized from battery through operated contacts lill, M2, and normal contacts lill, to ground, thus maintaining the X-delay relay ll operated during the period of the application of the rst group of dial impulses even though the operating circuit for the X-delay relay l2@ from battery through its upper coil .llZhA is open at the then open and operated oli-normal contacts Mlll of the selector switch At the completion of the rst group of dial impulses, contacts lill are again closed and contacts lll?. opened to hreai; the operating circuit to the lower winding EMB cf the X-delay relay l2@ which allows such relay to restore.

The second group of dial impulses is then transmitted over the tip and ring conductors 22 and 23 to cause the calling relay loll to again respond by momentarily closing contacts lili? and lill). The aforementioned operation of release delay relay liu, which is slow to release, remains operated, of course, during the energizetion and impulsing of the calling bridge relay Mill. Therefore, upon the iirst restoration of the calling bridge relay 160 in response to the second group of dial impulses, ground is connected through operated contacts 113, now restored contacts i132, pulsing Contact ltl, normal contacts 137i, and selector switch wiper M2M to a selected one of the individual control conductors XMil-XMQ and thereover selectively operate the X-magnet of a particular group connector switch, shown in Fig. 4. Thus, the wipers of the group selector switch of Fig. 4 are moved in the `first direction by the alternate energizatiou and deenergization of the X-magnet (Fig. 4) in response to the number of impulses in the second group of impulses. Alsc at the time that the calling bridge relay 100 restores in response to the first impulse in the second group of impulses, the slow release relay l5@ is operated from battery through now closed contacts H3, operated contacts H2, and pulsing contacts 102 to ground. Relay ldtl being slow to release, remains operated during the transmission of the second group of impulses and opens circ at operated .contacts ll to prevent operation oi relay loll from ground through the XON common control conductor and the 'if-magnet of the selected group selector switch to battery. The aforementioned operation of the slow to release relay 150 also opens contacts 152 to prevent operation of relay 2li) during the application o the second group of dial impulses. Therefore, in response to the second group of dial impulses of the calling bridge relay lili), the selected group connector switch is operated oft-normal in the rst direction by the alternate energization and deenergization of its X-magnet over the selected individual control conductors XMO-XM).

At the end ot the second group of dial impulses, the slow to release relay l5@ is again restored since the pulsing contact 162 remains open for a period of time greater than the release time oi the relay Relay i550, upon restoring, closes contact itil which completes a circuit from battery at the then oli-normal group connector switch, through the Y-magnet coil7 the X-olf-normal contact XON, the X-oil-normal multipled control conductor 29, closed contacts 151, and the coil of relay 1.3i) to ground causing relay 13G to operate. rl`he amount ot current required to operate relay i353 as conducted through the aforementioned path in series with the if-magnet of the selected group connector switch does not energize the Y- magnet sumciently to operate the group connector switch ott-normal in the second direction. With relay 1.3i) now operated, the next restoration of the calling bridge relay lili) in response to the rst impulse in the third group of dial impulses completes a circuit from ground through operated contacts lill, closed contacts 122, los, operated contacts l32, normally closed contacts 212i, and the multipled X-otf-normal lead 29 through operated ott-normal contact XON and the Y-magnet of the selected group selector .switch to battery, thus energizing the Y-:nagnet and stepping only that group connector switch in the second direction. in such manner, a line is selected by the oit-normal movement in the second direction of the selected group selector switch. in response to the energize,- tion of the Y-rnagnet by the third group of dial impulses. During the transmission of the third group of dial impulses, the slow to release relay 150 again is energized to open contacts and close contacts i533 to transfer the operating circuit for relay i3@ through its operated and closed contacts i313 to battery. At the completion of the third group of dial impulses, therefore, only relay 150 restores since relay i3@ is held operated through the previous circuit or the normally closed contacts 151 and the X-oit-normal lead 29.

lt will rst be assumed that the lines to be selected by the particularly selected group connector switch of Fig. 4 are private lines not requiring the dialing of a party digit. Under such circumstances, the particular position of the minor switch himll and its Wiper .lv/Mil?) will connect through the jumaer wire M294, the sleeve test conductor 28 of the group connector switch to the busy test relay through a circuit to bc traced hereafter. lt should he pointed out, however, that relay 2li) is first operated from battery through normally closed contacts lift., operated contacts lift', normally closed contacts i552, and the Lott-normal multipled control conductor to the now closed v`Lofi-normal contact YON?. and ground of the group connector switch that is new oinorrnal in both the lirst and second directions. Relay 210 locks up through operated contacts Zlii to the ground provided by operated contacts 115 of the release delay assises relay 110. With relay 210 operated, the circuit is now complete from the sleeve conductor 28 of the group connector switch that is ofi-normal in both the first and second directions, operated contacts 214, selector switch jumper M264-, selector switch wiper M203, normally closed contacts 154 to the coil of the busy test relay 200 and battery. It will be remembered that the switch train being specifically described is a busy verification system and if the line now selected is busy, ground will be present on its sleeve conductor to energize and operate the busy` test relay 26@ through the aformentioned circuit.`

it is not desired to permit everyone having access to to the subject circuits to switchthrough to a busy line unless they should be a busy verification operator or other authorized person. Assume that a busy veriication operator is extending the call and operating the circuits as described, the operator at her operators circuit (not shown) will connect battery to the hunt sleeve conductor 2S which is connected through normally closed contacts 201 to the lower winding 140B of relay 140 and ground to cause relay 140 to operate. Relay 140, when operated, is locked to battery through its upper winding 140A, operated contacts 141 and operated contacts M5 of the release delay relay 110 to ground. As soon as the busy test relay 200 operates upon connection to a husy line, contacts 201 are opened and contacts 202 are closed to connect resistance battery as provided from battery through the resistance R100 and the normally` closed contacts 155 to the HS conductor 25 therebyv signaling the operator that a busy line has been connected with. At the same time that the busy test relay 200 operates, the switchthrough relay 220 will be operated from battery through its winding, operated contacts 203, normal contacts 156, operated contacts 142 and through operated contacts 115 of the release delay relay to ground. Theq operation of the switchthrough relay 220 `closes contacts 221 and 222 to connect the talking conductors 22 and 23 to the multipled tip and ring of conductors of the group connector switches and therefore the tip and ring brushes of the selected group connector switch as operated into contact with the selected busy line. Thus the verication operator is enabled topmonitor the busy line and converse, if necessary. The aforementioned operation of the switchthrough relay 220 also opens contacts 223 to prevent any operation of the release magnet MZ of the selector switch M283 so long as the switch through relay 22@ remains energized.

t the completion of the call, the operator will hang up to restore the calling bridge relay 100 and the release delay relay 110, thus effecting a release of the remaining operated relays and switches in a conventional manner through the opening of various holding grounds and the energizations of the release magnets MZ and Z as will be obvious to anyone skilled in the'art.

it will now be assumed that the particularly selected group connector switch of Fig. 4 is one having access to a group of party lines for which a party digit must be absorbed. In such circumstances, there will be no jumper connection M204 and therefore the connection from the sleeve conductor of the group connector switch to the busy test relay 200 must be extended through operated contacts 214 of relay 210 and operated contacts 157 of relay 150. Relay 150, however, is restored at the end of the third group of dial impulses and will not be reoperated until application of a fourth group` of dial impulses causing consequent operation and release of the calling bridge relay mit. More speciically, at the conclusion of the third group of dial impulses, relay 210 will be operated and locked, as previously described, from the ground originally appearing on the Y-ofmormal multipled control conductor 3d due to the oit-normal position of the selected group selector switch in the second direction. Thereafter, when the first impulse of the fourth group of dial impulses causes the calling bridge relay 100 to restore and again operate, the slow to release relay 150 will again be operated to remain operated during the entire group of fourth impulses. However, at this time no pulsing path is prepared to any of the individual or common control conductors so that the group connector switch of Pig. 4 remains at the previously selected position in both the rst and second directions. Therefore, if the selected line is busy and ground is appearing on its sleeve terminal, ground will be connected over the multipled control sleeve conductor It?? through operated contacts 214 and now operated contacts ifi? of the slow to release relay 150 to canse the busy test relay 200 to operate. Busy test relay Zitti then locks up over operated contacts 204 so that it will remain operated after the slow to release relay 150 restores at the end of the transmission of the fourth group of dial impulses. This holding path is from battery through winding of busy test relay 200, normal contacts E54, and operated contacts 204 and 214 to the sleeve conductor of the busy line.

ln the foregoing, one detailed version of the impulse4 responsive automatic switching system of the invention has been described in connection with its application to a busy verification switch train. principles of the invention may be applied to any impulseresponsive automatic switch train whether it be used as a verification switching train for telephone systems or not.. The principal feature of the invention, as described, is the use of both individual and multipled control conductors responding to a first selection of an individual control conductor for moving the particular connector switch oit-normal in a first direction and thereafter responsive over the multipled control conductors to move the particular o-normal switch off-normal again in the secondv direction and complete the selection of a line.

Various modiiications may be made within the spirit of the invention and the scope of the appended claims.

What is claimed is:

l. In a telephone system, a plurality of groups of lines, an impulse responsive connector switch for each group of lines, talking conductors connected in multiple to each connector switch, a control conductor connected in multiple to each connector switch, an individual control conductor ,connected to each of said connector :switches respectively, an impulse responsive switch operative to select one of said individual control conductors, and means operative over said selected individual control conductor to cause the connector switch individual thereto to respond to impulses transmitted over said multipled control conductor and select a line in a particular group of lines.

2. In a telephone system, a plurality of groups of lines, an impulse responsive two-motion connector switch for each group of lines, talking conductors connected in multiple to each connector switch, a control conductor connected in multiple to each connector switch, an individual control conductor connected to each of said connector switches respectively, an impulse responsive selector switch operative to select one of said individual control l conductors, means to transmit a group of impulses to said selector switch to cause said switch to selectively connect with an individual control conductor, means to transmit a group of impulses over said selected individual control conductor to cause the connector switch individual thereto to move off-normal in a first direction, means responsive to the off-normal position in the first direction of a respective one of said connector switches to cause said respective switch only to respond to a group of impulses transmitted over said multipled control conductor, and means to transmit a group of impulses over said multipled control conductor to cause said respective switch to .move ntf-normal in a second direction to select a line in a particular group of lines.

3. ln a telephone system, a plurality of groups of lines, an impulse responsive twomotion connector switch for each group of lines, talking conductors connected in multiple to each connector switch, a plurality of control conductors connected in multiple to each connector switch,

lt is obvious that the t an individual control conductor connected to each ofsaid connector switches respectively, an impulse responsive selector switch operative to select one of said individual control conductors, means to transmit a group of impulses to said selector switch to cause said switch to selectively connect with an individual control conductor, means to transmit a group ot impulses over said selected individual control conductor to cause the connector switch individual thereto to move oli-normal in a irst direction, means re sponsive 'to the ofi-normal position in the direction of a respective one of said connector switches to cause said respective switch only to respond to a group of impulses transmitted over one of said multipled control conductors, means to transmit a group of impulses over said one multipled control conductor to cause said respective switch to move od-norrnal in a second direction to select a line in a particular group of lines, and mear controlled over a second oi said control conductors for restoring an off-normal one of said connector switches to normal.

4. ln a telephone system, a plurality of groups of lines, an impulse responsive two-motion connector switch for each group of lines, talking conductors connected in multiple to each connector switch, a plurality of control conductors connected in multiple to each connector switch, an individual control conductor connected to each of said connector switches respectively, an impulse responsive selector switch operative to select one of said individual control conductors, means to transmit a group of impulses to said selector switch to cause said switch to selectively connect with an individual control conductor, means to transmit a group of impulses over said selected individ ductor to lcause the connector switch individual thereto to move c `rrnal in a first direction, means responsive to the othnormal position in the rst direction oi a respective one of said connector switches tc cause said respective switch only to respond to a group ot impulses transmitted over one of said multipled control conductors, means to transmit a group of impulses over multipled control conductor to cause said respective switch to move ofinormal in a second direction to select a line in a particular group of lines, and means resp-on e to the idle or husy condition of a selected line "n a pa;tlcular grotg of lines to control over a second one of said multipled control conductors the operation of a ousy signal device,

5. ln a telephone system, a plurality oi groups of lines` an impulse responsive twosmotion conne tor switch for each group oi lines, talking conductors connected in multiple 'to each connector switch, a plurality of control ple to each connector switch, or connected to each ot said connector switches respectively, an impulse responsive selector switch operative to select of said individualv control conductors, means s trat mit a up of impulses 'to said selector switch to cause said switch to selectively connect with an individual control conductor, means to transmit a group of impulses over said selected individual control conductor to cause the connector switch individual thereto to move ofi-normal in a first direction, means responsive to the oilnormal positi'm in the iirst direction ot a respective one of said coi. ctor switches to cause said respective switch only to respond to a group of impulses transmitted over one ot said multipled control conductors, mecM s to transmit group of impulses over said multpled control conductor to said respective switch to move oil-normal in a second direction to select a 3 in a carticular group of lines, and means responsive to an cit-n mal position of a connector switch in the second direction and controlled over a second one of said rnultipled control conductors to prevent the transmission ol? additional groups of impulses over said one multipled control conductor to said connector witches.

6.' ln a telephone system, pl lity oi' groups of lines, an impulse rospo s two-motion connector switch for c each group of lines, talking conductors connected in multiple toeach connector switch, a plurality of control conductorsv connected in' multiple to each connector switch, an' individual control conductor connected to each of said connector switches respectively, an impulse responsive selector switch operative to select one oi said individual control conductors,` means to transmit a group of irnpulses to said selector switch to cause said switch to selectively connect with an individual control conductor, means to transmit a group of impulses over said selected individual control conductor to cause the connector switch individual thereto to move odi-normal in a iirst direction, means responsive to the oli-normal position in the lirst direction of a respective one of said connector switches to cause said respective switch only to respond to a group of impulses transmitted over one of said multipled con trol conductors, means to transmit a group of impulses over said one multipled control conductor to cause said respective switch to move olli-normal in a second direction to select a line in a particular group of lines, means controlled overa second of said control conductors for restoring an olnormal one of said connector switches to normal, and means responsive to the idle or busy condition of a selected line in a particular group of lines to control over a third one of said multipled control conductors the operation ot a busy signal device.

7. ln a telephone system, a plurality of groups of lines, an impulse responsive two-motion connector switch for each group of lines, talking conductors connected in multiple to each connector switch, a plurality of control conductors connected in multiple to each connector switch, an individual control conductor connected to each of said connector switches respectively, an impulse responsive selectorv switch operative to select one of said individual control conductors, means to transmit a group of impulses to said selector switch to cause said switch to selectively connect with an individual control conductor, means to transmit a group of impulses over said selected individual control conductor to cause the connector switch individual thereto to move olf-normal in a first direction, means responsive to the off-normal position in the first direction of a respective one of said connector switches to cause said respective switch only to respond to a groupk of impulses transmitted over one of said multipled control conductors, means to transmit a group of impulses over said one multipled control conductor to cause said respective switch to move off-normal in a second direction to select a line in a particular group of lines, means controlled over a second of said control conductors for restoring an olf-normal one of said connector switches to normal, and means responsive to an olf-normal 'position of a connector switch in the second direction and controlled over a third one of said multipled control conductors to prevent the transmission of additional groups of impulses over said one multipled control con ductor to said connector switches.

8. In a telephone system, a plurality of groups of lines, an impulse responsive two-motion connector switch for each group of lines, talking conductors connected in multiple to each connector switch, a plurality of control conductors connected in multiple to each connector switch, an individual control conductor connected to each of said connector switches respectively, an impulse responsive selector switch operative to select one of said individual control conductors, means to transmit a group of impulses to said selector `switch to cause said switch to selectively connect with an individual control conductor, means to transmit a group of impulses over said selected individual control conductor to cause the connector switch individual thereto to move oil-normal in a rst direction, means responsive to the olf-normal position in the iirst direction of a respective one of said connector switches to cause saidrespective switch only `to respond to a group of-impulses transmitted over one of said multipled control conductors, means to transmit a group of impulses over said one multiple control .conductor to cause said respective switch to move off-normal in a second direction to select a line in a particular group of lines, means responsive to the idle or busy condition of a selected line in a particular group of lines to control over a second one of said multipled control conductors the operation of a busy signal device, and means responsive to an off-normal position of a connector switch in the second direction and controlled over a third one ot said multipled control conductors to prevent the transmission of additional groups of impulses over said one multipled control conductor to said connector switches.

9. In a telephone system, a plurality of groups of lines, an impulse responsive two-motion connector switch for each group of lines, talking conductors connected in multiple to each connector switch, a plurality of control conductors connected in multiple to each connector switch, an individual control conductor connected to each of said connector switches respectively, an impulse responsive selector switch operative to select one of said individual control conductors, means to transmit a group of impulses to said selector switch to cause said switch to selectively connect with an individual control conductor, means to transmit a group of impulses over said selected individual control conductor to cause the connector switch individual thereto to move off-normal in a rst direction, means responsive to the off-normal position in the first direction of a respective one of said connector switches to cause said respective switch only to respond to a group of impulses transmitted over one of said multipled control conductors, means to transmit a group of impulses over said one multipled control conductor to cause said respective switch to move oit-normal in a second direction to select a line in a particular group of lines, means controlled over a second of said control conductors for restoring an oit-normal one of said connector switches to normal, means responsive to the idle or busy condition of a selected line in a particular group of lines to control over a third one of said multipled control conductors the operation of a busy signal device, and means responsive to an off-normal position of a connector switch in the second direction and controlled over a fourth one of said multipled control conductors to prel,

vent the transmission of additional groups of impulses over said one multipled control conductor to said connector switches.

l0. In a telephone system, a plurality of groups of lines, an impulse responsive two-motion connector switch for each group of lines, talking conductors connected in multiple to each connector switch, a plurality of control conductors connected in multiple to each connector switch, an individual control conductor connected to each of said connector switches respectively, an impulse responsive switch operative in response to a irst group of impulses to select one of said individual control conductors, means operative over said selected individual control conductor to cause the connector switch individual thereto to move olf-normal in a iirst direction in response to a second group of impulses, means responsive to the ot-normal position in the rst direction of a respective one of said connector switches to cause said respective switch only to respond to a third group of impulses trans mitted over a first of said multipled control conductors and move olf-normal in a second direction to select a line in a particular group of lines, and means operative in response to an off-normal position of the respective connector switch in the second direction to control over a second of said control conductors and prevent the transsion of additional groups of impulses over said first control conductor to the connector switches.

l1. In a telephone system, a plurality of groups of lines, an impulse responsive two-motion connector switch for each group of lines, talking conductors connected in multiple to each connector switch, a plurality of control conductors connected in multiple to each connector' switch, an individual control conductorl connected to each of said connector switches respectively, and impulse responsive selector switch operative in response to a first group of impulses to select one of said individual control conductors, means operative over said Selected individual control conductor to cause the connector switch individual thereto to move oit-normal in a rst direction in response to a second group of impulses, means responsive to the oit-normal position in the first direction of a respective one of said connector switches to cause said respective switch only to respond to a third group of impulses transmitted over a first of said multipled control conductors and move olf-normal in a second direction to select a line in a particular group of lines, means operative in response to an olf-normal position of the respective connector switch in the second direction to control over a second of said control conductors and prevent the transmission of additional groups of impulses over said iirst control conductor to the connector switches, and means responsive to the operation of said selector switch to a predetermined position to determine the idle or busy condition of a line selected by the respective connector switch at the termination of the transmission of the third group of impulses over the rst of said multipled conductors.

12. ln a telephone system, a plurality of groups of lines, an impulse responsive two-motion connector switch for each group of lines, talking conductors connected in multiple to each connector switch, a plurality of control conductors connected in multiple to each connector switch, an individual control conductor connected to each of said connector switches respectively, an impulse responsive selector switch operative in response to a iirst group of impulses to select one of said individual control conductors, means operative over said selected individual control conductor to cause the connector switch individual thereto to move oinormal in a rst direction in response to a second group of impulses, means responsive to the oit-normal position in the first direction of a respective one of said connector switches to cause said respective switch only to respond to a third group of irnpulses transmitted over a iirst of said multipled control control conductors and move off-normal in a second dif rection to select a line in a particular group of lines, and

References Cited in the le of this patent UNlTED STATES PATENTS Kessler Aug. 14, 1951 Kessler et al. a Dec. 30, 1952 UNITE STATES EATENT QFFICE CERTIFI Mmmm 831930 April 229 1958 .'t is hereby @@ftfied thai; @wor appam in th@ prnd spcfeaion of Title above numbered pal-bent mqurng @orae'ton and that the said, Lfttema Panam, read a5 corretfgd "melowu ("Eolulfmf?y lin@ 3% after "over" n-swt ma Said. ma; Column @M lin@ 25 for "multiple" read w mulgpld fm; @011mm T139 line 12,3 for "and" mad u an un I' V Sign@ and sealed 'ialm` 6th day of January 1.95%

` Attest:

mm1-L.' ARME ROBERT C. WATSON A'beabingV-Officer l Carmissioner of Patents 

